Molecular mechanism underlying the TLR4 antagonistic and antiseptic activities of papiliocin, an insect innate immune response molecule.

SignificanceSimilar to mammalian TLR4/MD-2, the Toll9/MD-2-like protein complex in the silkworm, Bombyx mori, acts as an innate pattern-recognition receptor that recognizes lipopolysaccharide (LPS) and induces LPS-stimulated expression of antimicrobial peptides such as cecropins. Here, we report that papiliocin, a cecropin-like insect antimicrobial peptide from the swallowtail butterfly, competitively inhibits the LPS-TLR4/MD-2 interaction by directly binding to human TLR4/MD-2. Structural elements in papiliocin, which are important in inhibiting TLR4 signaling via direct binding, are highly conserved among insect cecropins, indicating that its TLR4-antagonistic activity may be related to insect Toll9-mediated immune response against microbial infection. This study highlights the potential of papiliocin as a potent TLR4 antagonist and safe peptide antibiotic for treating gram-negative sepsis.

Bilateral subthalamic nucleus deep brain stimulation is an effective treatment for diphasic dyskinesia.

BACKGROUND AND PURPOSE: The purpose was to assess the effect of bilateral subthalamic nucleus deep brain stimulation (STN DBS) on diphasic dyskinesia in patients with Parkinson disease (PD) and to assess the factors associated with the remission of diphasic dyskinesia. METHODS: Medical records for PD patients who underwent bilateral STN DBS at the Movement Disorder Center of Seoul National University Hospital from March 2005 to November 2016 were reviewed. Patients were evaluated preoperatively and at 3, 6 and 12 months after surgery, and annually thereafter. The presence of peak-dose dyskinesia and diphasic dyskinesia is based on the interview and examination of patients at baseline and at each follow-up. RESULTS: Amongst 202 patients who underwent STN DBS, 66 patients who had diphasic dyskinesia preoperatively were included in the analysis. Diphasic dyskinesia disappeared in 49 (74%) after surgery. In 27 (55.1%) patients whose diphasic dyskinesia disappeared after DBS, peak-dose and diphasic dyskinesia disappeared persistently from as early as 3 months postoperatively. Age at onset was younger and disease duration at surgery was longer in patients whose diphasic dyskinesia persisted compared with patients whose diphasic dyskinesia disappeared. Multivariate Cox regression analysis demonstrated that patients with greater postoperative decrease of dopaminergic medications were more likely to have remission of diphasic dyskinesia. CONCLUSION: This study showed that bilateral STN DBS is effective in controlling diphasic dyskinesia and should be considered in PD patients with diphasic dyskinesia.

Urinary Symptoms and Urodynamic Findings in Patients with Spinocerebellar Ataxia.

Urinary dysfunctions are not considered symptoms of spinocerebellar ataxias (SCAs). However, given that a patient with SCAs without a family history might be misdiagnosed as MSA-C when having urinary dysfunctions, characterization of urinary dysfunctions in SCAs is needed not only to understand SCAs but also to correctly diagnosis patients with ataxia. We retrospectively reviewed medical records of 143 patients with genetically confirmed SCA1, 2, 3, 6, 7, 17, and DRPLA. Twenty-two patients (men n = 9; age 62.1 ± 10.9; disease duration 8.2 ± 2.9 years) who had lower urinary track symptoms (LUTS) were included in this study. Six patients underwent urodynamic study (UDS), and 2 underwent uroflowmetry. LUTS was present in 1 of 11 patients with SCA1, in 4 of 51 with SCA2, in 2 of 26 with SCA3, in 3 of 20 with SCA6, in 2 of 4 with SCA7, in 8 of 26 with SCA17, and in 2 of 5 with DRPLA. Overall, urinary frequency was the most common symptom (16 patients, 72.7%) followed by voiding difficulty. In three of the 6 patients with UDS, post-micturition residuals were > 100 ml. Detrusor overactivity was noted in three patients. Detrusor areflexia was observed in one. Four patients were diagnosed with a neurogenic bladder, 3 with a storage problem, and 1 with both storage and voiding problems. Fifteen percent of the patients with SCAs had LUTS, and LUTS occurred in various types of SCAs. Our results indicate that SCAs should be considered in patients with progressive cerebellar ataxia and urinary dysfunctions.

Increased Diagnostic Yield of Spastic Paraplegia with or Without Cerebellar Ataxia Through Whole-Genome Sequencing.

Inherited disorders of spasticity or ataxia exist on a spectrum with overlapping causative genes and phenotypes. We investigated the use of whole-genome sequencing (WGS) to detect a genetic cause when considering this spectrum of disorders as a single group. We recruited 18 Korean individuals with spastic paraplegia with or without cerebellar ataxia in whom common causes of hereditary cerebellar ataxia and hereditary spastic paraplegia had been excluded. We performed WGS with analysis for single nucleotide variants, small insertions and deletions, copy number variants (CNVs), structural variants (SVs) and intronic variants. Disease-relevant variants were identified in ABCD1 (n = 3), CAPN1 (n = 2), NIPA1 (n = 1) and PLA2G6 (n = 1) for 7/18 patients (38.9%). A 'reverse phenotyping' approach was used to clarify the diagnosis in individuals with PLA2G6 and ABCD1 variants. One of the ABCD1 disease-relevant variants was detected on analysis for intronic variants. No CNV or SV causes were found. The two males with ABCD1 variants were initiated on monitoring for adrenal dysfunction. This is one of only a few studies to analyse spastic-ataxias as a continuous spectrum using a single approach. The outcome was improved diagnosis of unresolved cases for which common genetic causes had been excluded. This includes the detection of ABCD1 variants which had management implications. Therefore, WGS may be particularly relevant to diagnosing spastic ataxias given the large number of genes associated with this condition and the relatively high diagnostic yield.

Antiseptic Effect of Ps-K18: Mechanism of Its Antibacterial and Anti-Inflammatory Activities.

Recently, bioactive peptides have attracted attention for their therapeutic applications in the pharmaceutical industry. Among them, antimicrobial peptides are candidates for new antibiotic drugs. Since pseudin-2 (Ps), isolated from the skin of the paradoxical frog Pseudis paradoxa, shows broad-spectrum antibacterial activity with high cytotoxicity, we previously designed Ps-K18 with a Lys substitution for Leu18 in Ps, which showed high antibacterial activity and low toxicity. Here, we examined the potency of Ps-K18, aiming to develop antibiotics derived from bioactive peptides for the treatment of Gram-negative sepsis. We first investigated the antibacterial mechanism of Ps-K18 based on confocal micrographs and field emission scanning electron microscopy, confirming that Ps-K18 targets the bacterial membrane. Anti-inflammatory mechanism of Ps-K18 was investigated by secreted alkaline phosphatase reporter gene assays and RT-PCR, which revealed that Ps-K18 activates innate defense via Toll-like receptor 4-mediated nuclear factor-kappa B signaling pathways. Moreover, we investigated the antiseptic effect of Ps-K18 using a lipopolysaccharide or Escherichia coli K1-induced septic shock mouse model. Ps-K18 significantly reduced bacterial growth and inflammatory responses in the septic shock model. Ps-K18 showed low renal and liver toxicity and attenuated lung damage effectively. This study suggests that Ps-K18 is a potent peptide antibiotic that could be applied therapeutically to Gram-negative sepsis.

The prevalence of non-troublesome dyskinesia in Parkinson's disease.

INTRODUCTION: Levodopa-induced dyskinesia is a common complication of long-term treatment of Parkinson's disease (PD), but its impact on daily activities is somewhat controversial. This study investigated the prevalence and severity of dyskinesia, particularly non-troublesome dyskinesia, to provide insights into its significance for long-term PD management. METHODS: We reviewed electronic medical records of 2571 PD patients, who had been followed up at Seoul National University Hospital and were seen between January 2016 and June 2017. Dyskinesia severity had been assessed during follow-up and was recorded with the highest score by considering its impact on functioning (0 = no dyskinesia, 1 = minimal with patient unaware, 2 = mild disability, 3 = moderate disability, 4 = severe disability). RESULTS: The prevalence of dyskinesia increased progressively with longer PD duration; 8.2% in the group with disease duration of 0-5 years, 40.7% for 6-10 years, 66.0% for 11-15 years, 74.6% for 16-20 years, and 83.2% for 21 years or more. The prevalence of dyskinesia scores ≥2 also increased with disease duration, with rates of 6.3% for 0-5 years, 31.9% for 6-10 years, 54.8% for 11-15 years, 62.9% for 16-20 years and 73.7% for 21 or more years. CONCLUSION: Despite the increasing prevalence and severity of dyskinesia with longer PD duration, the study found that less than non-troublesome dyskinesia remained at approximately 26.3% even after more than 21 years of disease duration. These findings suggest that dyskinesia may not be troublesome for many PD patients even in long-term.

Analysis of HTT CAG repeat expansion among healthy individuals and patients with chorea in Korea.

BACKGROUND: Although the epidemiology of Huntington's disease (HD) in Korea differs notably from that in Western countries, the genetic disparities between these regions remain unclear. OBJECTIVE: To investigate the characteristics and clinical significance of cytosine-adenine-guanine (CAG) repeat size associated with HD in the Korean population. METHODS: We analyzed the CAG repeat lengths of the HTT gene in 941 healthy individuals (1,882 alleles) and 954 patients with chorea (1,908 alleles) from two referral hospitals in Korea. We presented normative CAG repeat length data for the Korean population and computed the reduced penetrance (36-39 CAG) and intermediate allele (27-35 CAG) frequencies in the two groups. Furthermore, we investigated the relationship between intermediate alleles and chorea development using logistic regression models in individuals aged ≥55 years. RESULTS: The mean (±standard deviation) CAG repeat length in healthy individuals was 17.5 ± 2.0, with a reduced penetrance allele frequency of 0.05 % (1/1882) and intermediate allele frequency of 0.69 % (13/1882). We identified 213 patients with genetically confirmed HD whose CAG repeat length ranged from 39 to 140, with a mean of 45.2 ± 7.9 in the longer allele. Compared with normal CAG repeat alleles, intermediate CAG repeat alleles were significantly related to a higher risk of developing chorea (age of onset range, 63-84 years) in individuals aged ≥55 years. CONCLUSIONS: This study provides insights into the specific characteristics of CAG repeat lengths in the HTT gene in the Korean population. The reduced penetrance and intermediate allele frequencies in the Korean general population seem to be lower than those reported in Western populations. The presence of intermediate alleles may increase the risk of chorea in the Korean elderly population, which requires further large-scale investigations.

Impact of the coronavirus disease 2019 pandemic on the incidence of other infectious diseases in the hematology hospital in Korea.

BACKGROUND/AIMS: Since the coronavirus disease 2019 (COVID-19) outbreak, hospitals have implemented infection control measures to minimize the spread of the virus within facilities. This study aimed to investigate the impact of COVID-19 on the incidence of healthcare-associated infections (HCAIs) and common respiratory virus (cRV) infections in hematology units. METHODS: This retrospective study included all patients hospitalized in Catholic Hematology Hospital between 2019 and 2020. Patients infected with vancomycin-resistant Enterococci (VRE), carbapenemase-producing Enterobacterales (CPE), Clostridium difficile infection (CDI), and cRV were analyzed. The incidence rate ratio (IRR) methods and interrupted time series analyses were performed to compare the incidence rates before and after the pandemic. RESULTS: The incidence rates of CPE and VRE did not differ between the two periods. However, the incidence of CDI increased significantly (IRR: 1.41 [p = 0.002]) after the COVID-19 pandemic. The incidence of cRV infection decreased by 76% after the COVID-19 outbreak (IRR: 0.240 [p < 0.001]). The incidence of adenovirus, parainfluenza virus, and rhinovirus infection significantly decreased in the COVID-19 period (IRRs: 0.087 [p = 0.003], 0.031 [p < 0.001], and 0.149 [p < 0.001], respectively). CONCLUSION: The implementation of COVID-19 infection control measures reduced the incidence of cRV infection. However, CDI increased significantly and incidence rates of CPE and VRE remained unchanged in hematological patients after the pandemic. Infection control measures suitable for each type of HCAI, such as stringent hand washing for CDI and enough isolation capacities, should be implemented and maintained in future pandemics, especially in immunocompromised patients.

Impact of Complete or Incomplete Revascularization for Left Main Coronary Disease: The Extended PRECOMBAT Study.

Background: Whether complete revascularization (CR) or incomplete revascularization (IR) may affect long-term outcomes after PCI) and coronary artery bypass grafting (CABG) for left main coronary artery (LMCA) disease is unclear. Objectives: The authors sought to assess the impact of CR or IR on 10-year outcomes after PCI or CABG for LMCA disease. Methods: In the PRECOMBAT (Premier of Randomized Comparison of Bypass Surgery versus Angioplasty Using Sirolimus-Eluting Stent in Patients with Left Main Coronary Artery Disease) 10-year extended study, the authors evaluated the effect of PCI and CABG on long-term outcomes according to completeness of revascularization. The primary outcome was the incidence of major adverse cardiac or cerebrovascular events (MACCE) (composite of mortality from any cause, myocardial infarction, stroke, or ischemia-driven target vessel revascularization). Results: Among 600 randomized patients (PCI, n = 300 and CABG, n = 300), 416 patients (69.3%) had CR and 184 (30.7%) had IR; 68.3% of PCI patients and 70.3% of CABG patients underwent CR, respectively. The 10-year MACCE rates were not significantly different between PCI and CABG among patients with CR (27.8% vs 25.1%, respectively; adjusted HR: 1.19; 95% CI: 0.81-1.73) and among those with IR (31.6% vs 21.3%, respectively; adjusted HR: 1.64; 95% CI: 0.92-2.92) (P for interaction = 0.35). There was also no significant interaction between the status of CR and the relative effect of PCI and CABG on all-cause mortality, serious composite of death, myocardial infarction, or stroke, and repeat revascularization. Conclusions: In this 10-year follow-up of PRECOMBAT, the authors found no significant difference between PCI and CABG in the rates of MACCE and all-cause mortality according to CR or IR status. (Ten-Year Outcomes of PRE-COMBAT Trial [PRECOMBAT], NCT03871127; PREmier of Randomized COMparison of Bypass Surgery Versus AngioplasTy Using Sirolimus-Eluting Stent in Patients With Left Main Coronary Artery Disease [PRECOMBAT], NCT00422968).

One-pot synthesis of symmetrical and unsymmetrical aryl sulfides by Pd-catalyzed couplings of aryl halides and thioacetates.

Aryl sulfides were obtained from the coupling reaction of S-aryl (or S-alkyl) thioacetates and aryl bromides in the presence of palladium catalyst. This reaction method enables the one-pot synthesis of symmetrical and unsymmetrical diaryl sulfides by employing potassium thioacetate with aryl iodides and aryl bromides.

Comparison of Long-Term Outcomes Following Coronary Revascularization in Men-vs-Women with Unprotected Left Main Disease.

Gender differences have been recognized in several aspects of coronary artery disease (CAD). However, evidence for gender differences in long-term outcomes after left main coronary artery (LMCA) revascularization is limited. We sought to evaluate the impact of gender on outcomes after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) for unprotected LMCA disease. We evaluated 4,320 patients with LMCA disease who underwent CABG (n = 1,456) or PCI (n = 2,864) from the Interventional Research Incorporation Society-Left MAIN Revascularization registry. The primary outcome was a composite of death, myocardial infarction (MI), or stroke. Among 4,320 patients, 968 (22.4%) were females and 3,352 (77.6%) were males. Compared to males, females were older, had a higher prevalence of hypertension and insulin-requiring diabetes, more frequently presented with acute coronary syndrome, but had less extensive CAD and less frequent left main bifurcation involvement. The adjusted risk for the primary outcome was not different after PCI or CABG in females and males (hazard ratio [HR] 1.09; 95% confidence interval [CI]: 0.73-1.63 and HR 0.97; 95% CI: 0.80-1.19, respectively); there was no significant interaction between gender and the revascularization strategy (P for interaction = 0.775). In multivariable analysis, gender did not appear to be an independent predictor for the primary outcome. In revascularization for LMCA disease, females and males had a comparable primary composite outcome of death, MI, or stroke with either CABG or PCI without a significant interaction of gender with the revascularization strategy.

Phloretin Protects Macrophages from E. coli-Induced Inflammation through the TLR4 Signaling Pathway.

Macrophages are the cells of the first-line defense system, which protect the body from foreign invaders such as bacteria. However, Gram-negative bacteria have always been the major challenge for macrophages due to the presence of lipopolysaccharides on their outer cell membrane. In the present study, we evaluated the effect of phloretin, a flavonoid commonly found in apple, on the protection of macrophages from Escherichia coli infection. RAW 264.7 cells infected with standard E. coli, or virulent E. coli K1 strain were treated with phloretin in a dose-dependent manner to examine its efficacy in protection of macrophages. Our results revealed that phloretin treatment reduced the production of nitric oxide (NO) and generation of reactive oxygen species along with reducing the secretion of proinflammatory cytokines induced by the E. coli and E. coli K1 strains in a concentration-dependent manner. Additionally, treatment of phloretin downregulated the expression of E. coli-induced major inflammatory markers i.e. cyclooxygenase-2 (COX-2) and hemeoxygenase-1 (HO-1), in a concentration dependent manner. Moreover, the TLR4-mediated NF-κB pathway was activated in E. coli-infected macrophages but was potentially downregulated by phloretin at the transcriptional and translational levels. Collectively, our data suggest that phloretin treatment protects macrophages from infection of virulent E. coli K1 strain by downregulating the TLR4-mediated signaling pathway and inhibiting NO and cytokine production, eventually protecting macrophages from E. coli-induced inflammation.

Influence of bore fluid composition on the physiochemical properties and performance of hollow fiber membranes for ultrafiltration.

Porous hollow fiber polysulfone (PSf) membranes were fabricated via a phase-inversion process and their performance during ultrafiltration (UF) was evaluated. The effects of the composition and concentration (0-50%) of different bore fluid mixtures, including N-methyl-2-pyrrolidone (NMP)/water, glycerol (G)/water, and ethylene glycol (EG)/water (in comparison with pure deionized water), on the structure, physicochemical properties, and performance of the fabricated membranes was investigated. Using these various bore fluid mixtures altered the thermodynamic and kinetic properties of the phase inversion system, and changed the morphology and structure of the fabricated membranes, especially on the lumen side. Increasing concentrations of NMP, G, and EG in the bore fluid resulted in increased pore size, porosity, and hydrophilicity. These bore fluid mixtures exhibited a strong influence on the perm-selectivity of the as-spun hollow fiber membranes. The membrane fabricated using 50% NMP/water as the bore fluid mixture exhibited the highest water flux of 166.98 LMH with a bovine serum albumin rejection rate of more than 97%. Overall, this study introduces an easy and effective way to control the structure of the membrane through bore fluid modification and shows how the inner skin layer properties can have a remarkable effect on water permeance, even in the out-in filtration test.

Atherogenic index of plasma and the risk of advanced subclinical coronary artery disease beyond traditional risk factors: An observational cohort study.

BACKGROUND: Atherogenic lipoprotein profile of plasma is an important risk factor for atherosclerosis. The atherogenic index of plasma (AIP) has been suggested as a novel marker for atherosclerosis. HYPOTHESIS: AIP is a useful marker of advanced subclinical coronary artery disease (CAD) in subjects without overt renal dysfunction. METHODS: A total of 6928 subjects with estimated glomerular filtration rate > 60 mL/minutes/1.73 m2 evaluated by coronary computed tomography angiography (CCTA) for health check-up were included. The relation of AIP to advanced CAD (heavy coronary calcification, defined as coronary artery calcium score [CACS] >100 or obstructive coronary plaque [OCP], defined as plaque with >50% stenosis) was evaluated. RESULTS: All participants were stratified into four groups based on AIP quartiles. The prevalence of CACS >100 (group I [lowest] 4.7% vs group II 7.0% vs group III 8.8% vs group IV 10.0%) and OCP (group I 3.7% vs group II 6.4% vs group III 8.8% vs group IV 10.9%) (all P < .001) increased with elevating AIP quartiles. Higher AIP (per 0.1 unit increase) was associated with an increased risk of CACS >100 (odds ratio [OR] 1.057, 95% confidence interval (CI) 1.010 to 1.106, P = .017; relative risk (RR) 1.048, 95% CI 1.009-1.089, and P = .015) and OCP (OR 1.079, 95% CI 1.033-1.127, P = .001; RR 1.069, 95% CI 1.031-1.108, P < .001) after adjusting for age > 60 years, male sex, hypertension, diabetes mellitus, dyslipidaemia, obesity, and proteinuria. CONCLUSION: AIP is independently associated with advanced subclinical CAD beyond traditional risk factors.

Identification of inhibitor binding hotspots in Acinetobacter baumannii ß-ketoacyl acyl carrier protein synthase III using molecular dynamics simulation.

Acinetobacter baumannii is a gram-negative bacterium that is rapidly developing drug resistance due to the abuse of antibiotics. The emergence of multidrug-resistant A. baumannii has greatly contributed to the urgency of developing new antibiotics. Previously, we had discovered two potent inhibitors of A. baumannii ß-ketoacyl acyl carrier protein synthase III (abKAS III), YKab-4 and YKab-6, which showed potent activity against A. baumannii. In addition, we have reported the crystal structure of abKAS III. In the present study, we investigated the binding between abKAS III and its inhibitors by docking simulation. Molecular dynamics (MD) simulations were performed using docked inhibitor models to identify the hotspot residues related to inhibitor binding. The binding free energies estimated using the MD simulations suggest that residues I198 and F260 of abKAS III serve as the inhibitor binding hotspots. I198, found to be responsible for mediating hydrophobic interactions with inhibitors, had the strongest residual binding energy among all abKAS III residues. We modeled glutamine substitutions of residues I198 and F260 and estimated the relative binding energies of the I198Q and F260Q variants. The results confirmed that I198 and F260 are the key inhibitor binding residues. The roles of the key residues in inhibitor binding, i.e. F260 in the α9 helix and the I198 in the ß6ß7 loop region, were investigated using principal component analysis (PCA). PCA revealed the structural changes resulting from the abKAS III I198Q and F260Q mutations and described the essential dynamics of the α9 helix. In addition, the results suggest that the ß6ß7 loop region may act as a gate keeper for ligand binding. Hydrophobic interactions involving I198 and F260 in abKAS III appear to be essential for the binding of the inhibitors YKab-4 and YKab-6. In conclusion, this study provides valuable information for the rational design of antibiotics via the inhibition of abKAS III.

Patient selected goals and satisfaction after bilateral subthalamic nucleus deep brain stimulation in Parkinson's disease.

Assessing patient goals is crucial in understanding patient centered outcomes and satisfaction. However, patient goals may change throughout treatment. Our objective is to identify the changes in patient-selected goals of Parkinson's disease (PD) patients undergoing bilateral subthalamic nucleus deep brain stimulation (STN-DBS) and examine the relationship among patient-selected goal achievement, standard DBS outcome measures, and overall patient satisfaction. Seventy-five patients undergoing bilateral STN-DBS listed three patient-selected goals before surgery. After six months, patients were asked to restate the three goals and to rate the degree of goal achievement and the overall satisfaction of surgery. The three most frequently selected goals were "dyskinesia", "gait disorder", and "medication off duration". After six months, 80.0% of patients could not accurately recall their pre-DBS goals. "Dyskinesia" was the most consistently selected goal, more patients selected "tremor" and "less medication" at post-DBS compared to pre-DBS, and less patients selected "gait disorder" at post-DBS compared to pre-DBS. 74.7% of patients reported overall satisfaction by stating they were "very much" or "much better after surgery". Patient satisfaction significantly correlated with goal achievement (r = 0.640; p < 0.001). Interestingly, change in UPDRS motor scores did not correlate with patient satisfaction (r = 0.100; p = 0.395). Although recalled goals do not accurately represent the pre-surgical goals, the achievement score for recalled goals significantly correlated with patient satisfaction. Patient goals change due to many reasons. Therefore, follow-up patient counseling to discuss goals and outcomes is important in improving patient satisfaction after STN-DBS.

Palladium-catalyzed decarboxylative coupling of alkynyl carboxylic acids and aryl halides.

2-Octynoic acid and phenylpropiolic acid were employed for the palladium-catalyzed decarboxylative coupling reaction and with a variety of aryl halides. The former needed 1,4-bis(diphenylphosphino)butane (dppb) as a ligand and the latter tri-tert-butylphosphine (P(t)Bu(3)), and both required 2 equiv of tetra-n-butylammonium fluoride (TBAF) for full conversion. These reactions showed high reactivities and tolerance of functional groups such as vinyl, ester, ether, ketone, and amine.

Effects of C-Terminal Residues of 12-Mer Peptides on Antibacterial Efficacy and Mechanism.

The development of new antimicrobial agents is essential for the effective treatment of diseases such as sepsis. We previously developed a new short peptide, Pap12-6, using the 12 N-terminal residues of papiliocin, which showed potent and effective antimicrobial activity against multidrug-resistant Gram-negative bacteria. Here, we investigated the antimicrobial mechanism of Pap12-6 and a newly designed peptide, Pap12-7, in which the 12th Trp residue of Pap12-6 was replaced with Val to develop a potent peptide with high bacterial selectivity and a different antibacterial mechanism. Both peptides showed high antimicrobial activity against Gram-negative bacteria, including multidrug-resistant Gram-negative bacteria. In addition, the two peptides showed similar anti-inflammatory activity against lipopolysaccharide-stimulated RAW 264.7 cells, but Pap12-7 showed very low toxicities against sheep red blood cells and mammalian cells compared to that showed by Pap12-6. A calcein dye leakage assay, membrane depolarization, and confocal microscopy observations revealed that the two peptides with one single amino acid change have different mechanisms of antibacterial action: Pap12-6 directly targets the bacterial cell membrane, whereas Pap12-7 appears to penetrate the bacterial cell membrane and exert its activities in the cell. The therapeutic efficacy of Pap12-7 was further examined in a mouse model of sepsis, which increased the survival rate of septic mice. For the first time, we showed that both peptides showed anti-septic activity by reducing the infiltration of neutrophils and the production of inflammatory factors. Overall, these results indicate Pap12-7 as a novel non-toxic peptide with potent antibacterial and anti-septic activities via penetrating the cell membrane.

CSF ß-amyloid42 and risk of freezing of gait in early Parkinson disease.

OBJECTIVE: To determine whether CSF biomarkers can be used as a predictor of freezing of gait (FOG) in Parkinson disease (PD) and to investigate the predictive value of clinical, dopamine transporter (DAT) imaging, and CSF parameters both separately and in combination. METHODS: This study using the PPMI data included 393 patients with newly diagnosed PD without FOG at baseline. We evaluated CSF for ß-amyloid 1-42 (Aß42), α-synuclein, total tau, phosphorylated tau181, and the calculated ratio of Aß42 to total tau at baseline. Demographic and clinical data and DAT imaging results were also investigated. Cox proportional-hazards regression analyses were performed to identify the factors predictive of FOG. From these results, we constructed a predictive model for the development of FOG. RESULTS: During a median follow-up of 4.0 years, only Aß42 among the CSF biomarkers was associated with the development of FOG (hazard ratio 0.997, 95% confidence interval [CI] 0.996-0.999, p = 0.009). Postural instability gait difficulty (PIGD) score, caudate DAT uptake, and, to a lesser extent, male sex, Movement Disorders Society Unified Parkinson's Disease Rating Scale motor score, and Montreal Cognitive Assessment score were also predictive of FOG. The combined model integrating the PIGD score, caudate DAT uptake, and CSF Aß42 achieved a better discriminative ability (area under the curve 0.755, 95% CI 0.700-0.810) than any factor alone. CONCLUSION: We found CSF Aß42 to be a predictor of FOG in patients with early PD. Furthermore, the development of FOG within 4 years after diagnosis of PD can be predicted with acceptable accuracy with our risk model.